New Jersey Governor Chris Christie speaks during his annual State of the State address in Trenton, New Jersey January 14, 2014. Christie opened his State of the State Address on Tuesday with an apology and a vow to fully cooperate with "all appropriate" investigations of an apparent scheme to cause massive traffic jams as well as the use of federal money for a state ad campaign. [Photo/Agencies]

TRENTON, N.J.- New Jersey Governor Chris Christie offered a fresh apology and vowed to cooperate with an investigation into a traffic scandal rocking his administration, but mostly touted the state's bipartisan cooperation during a key speech on Tuesday.

Christie, a charismatic conservative and an early favorite in the Republican bid for the White House in 2016, used his State of the State address to list his conservative policy prescriptions, trying to leave two scandals behind.

"The last week has certainly tested this administration. Mistakes were clearly made. And as a result, we let down the people we are entrusted to serve," Christie said in opening his annual address. "Without a doubt, we will cooperate with all appropriate inquiries to ensure that this breach of trust does not happen again."

Re-elected in a landslide victory last November, he faces accusations that his aides orchestrated a bridge blocking to punish a political opponent, coupled with new allegations, pushed by a democratic lawmaker, over Christie's use of federal storm aid.

Two sets of emails last week appeared to show that aides planned lane closures for several days last September on a stretch of highway leading to the George Washington Bridge, which spans the Hudson River between New Jersey and Manhattan, and then lied about it.

Christie has denied any knowledge of the plan to snarl traffic at the bridge as political payback against the Democratic mayor of nearby Fort Lee, New Jersey, for his refusal to endorse Christie's gubernatorial bid.

The governor's speech mostly addressed the "Jersey Comeback" - which Christie has long claimed has resulted in private sector jobs growth and secured public-private investment in the Garden State - and his cooperation with the Democrat-controlled state legislature in this heavily Democratic state.

"No state in this country has shown more bipartisan cooperation and governance over the last four years than New Jersey, and our people are proud of it. Let's resolve today that we will continue to put those people first. We will do our jobs," Christie said.

"These are our achievements: Four balanced budgets. Passed with bipartisan support. Pension reform and tenure reform. Passed with bipartisan support. A cap on property taxes. Passed with bipartisan support," Christie said. "We acted, and we acted together."

Christie also gave a nod to an issue that was at the top of his agenda in his first term - an across-the-board tax cut - though he said he will wait to announce specific ideas when he gives his budget address next month.

He also vowed to tackle abuses in the state pension system.

The state's economy has seen signs of improvement over the last several months. Its unemployment rate experienced the largest monthly drop on record in November, dropping 0.6 percentage point to 7.8 percent, according to the state labor department.

Revenue has also been recovering steadily. In the first five months of fiscal 2014, which began on July 1, New Jersey took in 7.9 percent more revenue - from income, sales, corporate and other taxes - than in the same period the previous fiscal year. But that is still 1.2 percent, or $98 million, under budget.

Still, the state's fiscal situation and Christie's ideas for improving it could be overshadowed by his response to the scandals and speculation about his political future.

Since taking office four years ago, Christie - a former federal prosecutor - has built a national reputation as a Republican capable of winning bipartisan support for his conservative priorities, such as spending cuts, while repairing New Jersey's reputation for corruption and graft.